Addition of Bigger Numbers
In the previous lesson, we have learnt the addition of 1-digit and 2-digit numbers. Let's learn the addition of 3-digit numbers now.
Adding Two 3-Digit Numbers
(i) Without Regrouping
Add 130 and 147
Step 1: Arrange the numbers in columns.
130
+ 147
Step 2: Add the ones and write in ones place.
130
+ 147
7
Step 3: Add the tens and write in tens place.
130
+ 147
77
Step 4: Add the hundreds and write in hundreds place.
130
+ 147
277
130 + 147 = 277
130
+ 147
Step 2: Add the ones and write in ones place.
130
+ 147
7
Step 3: Add the tens and write in tens place.
130
+ 147
77
Step 4: Add the hundreds and write in hundreds place.
130
+ 147
277
130 + 147 = 277
(ii) With Regrouping
In the previous example, the adition was easy as in each step, the sum was less than 10.
Let's see another example.
Step 1: Arrange the numbers in columns.
257
+ 165
Step 2: Add the ones. 7 + 5 = 12. We write 2 in the once place of the sum and carry over 1 to the tens place. (regrouping ones)
1
257
+ 165
2
Step 3: Add the tens. 1 + 5 + 6 = 12. We write 2 in the tens place of the sum and carry over 1 to the hundreds place. (regrouping tens)
1
257
+ 165
22
Step 4: Add the hundreds. 1 + 2 + 1 = 4. We write 4 in the hundreds place
257
+ 165
422
257 + 165 = 422
257
+ 165
Step 2: Add the ones. 7 + 5 = 12. We write 2 in the once place of the sum and carry over 1 to the tens place. (regrouping ones)
1
257
+ 165
2
Step 3: Add the tens. 1 + 5 + 6 = 12. We write 2 in the tens place of the sum and carry over 1 to the hundreds place. (regrouping tens)
1
257
+ 165
22
Step 4: Add the hundreds. 1 + 2 + 1 = 4. We write 4 in the hundreds place
257
+ 165
422
257 + 165 = 422
Adding Three 3-Digit Numbers
(i) Without Regrouping
Add 212, 434 and 343
Step 1: Arrange the numbers in columns.
212
434
+ 343
Step 2: Add the ones and write in ones place.
212
434
+ 343
9
Step 3: Add the tens and write in tens place.
212
434
+ 343
89
Step 4: Add the hundreds and write in hundreds place.
212
434
+ 343
989
212 + 434 + 343 = 989
212
434
+ 343
Step 2: Add the ones and write in ones place.
212
434
+ 343
9
Step 3: Add the tens and write in tens place.
212
434
+ 343
89
Step 4: Add the hundreds and write in hundreds place.
212
434
+ 343
989
212 + 434 + 343 = 989
(ii) With Regrouping
In the previous example, the adition was easy as in each step, the sum was less than 10.
Let's see another example.
Step 1: Arrange the numbers in columns.
164
275
+ 243
Step 2: Add the ones. 4 + 5 + 3 = 12. We write 2 in the once place of the sum and carry over 1 to the tens place. (regrouping ones)
1
164
275
+ 243
2
Step 3: Add the tens. 1 + 6 + 7 + 4 = 18. We write 8 in the tens place of the sum and carry over 1 to the hundreds place. (regrouping tens)
1
164
275
+ 243
82
Step 4: Add the hundreds. 1 + 1 + 2 + 2 = 6. We write 6 in the hundreds place
164
275
+ 243
682
164 + 275 + 243 = 682
164
275
+ 243
Step 2: Add the ones. 4 + 5 + 3 = 12. We write 2 in the once place of the sum and carry over 1 to the tens place. (regrouping ones)
1
164
275
+ 243
2
Step 3: Add the tens. 1 + 6 + 7 + 4 = 18. We write 8 in the tens place of the sum and carry over 1 to the hundreds place. (regrouping tens)
1
164
275
+ 243
82
Step 4: Add the hundreds. 1 + 1 + 2 + 2 = 6. We write 6 in the hundreds place
164
275
+ 243
682
164 + 275 + 243 = 682